P2242

3UR-FE ENGINE CONTROL: SFI SYSTEM: P2237-P2239, P2240-P2242, P2252, P2253, P2255, P2256: Oxygen (A/F) Sensor Pumping Current Circuit / Open (Bank 1 Sensor 1)


DESCRIPTION

Refer to DTC P2195 P2195.





HINT
* DTCs P2238, P2239, P2252 and P2253 indicate malfunctions related to the bank 1 A/F sensor circuit.
* DTCs P2241, P2242, P2255 and P2256 indicate malfunctions related to the bank 2 A/F sensor circuit.

MONITOR DESCRIPTION

These DTCs are stored when there is an open or short in the A/F sensor circuit, or if A/F sensor output drops.

To detect these problems, the voltage of the A/F sensor is monitored when turning the engine switch on (IG), and the admittance (admittance is an electrical term that indicates the ease of flow of current) is checked while driving. If the voltage of the A/F sensor is between 0.6 V and 4.5 V, it is considered normal. If the voltage is outside of the specified range, or the admittance is less than the standard value, the ECM will determine that there is a malfunction in the A/F sensor. If the same malfunction is detected in the next driving cycle, the MIL is illuminated and a DTC is stored.

The Air-Fuel Ratio (A/F) sensor varies its output voltage in proportion to the air-fuel ratio. If the A/F sensor impedance (alternating current resistance) or output voltage deviates greatly from the standard range, the ECM determines that there is an open or short in the A/F sensor circuit.

MONITOR STRATEGY





TYPICAL ENABLING CONDITIONS

P2237, P2238, P2240 and P2241:





P2239, P2242, P2252, P2253, P2255 and P2256:





P2237 and P2240 (A/F sensor - Open circuit between A1A+ and A1A-/A2A+ and A2A-):





P2238 and P2241 (A/F sensor - Low impedance):





Others:





TYPICAL MALFUNCTION THRESHOLDS

P2237 and P2240 (Open circuit between A1A+ and A1A-/A2A+ and A2A-):





P2238 and P2241 (Low impedance):





P2238 and P2241 (Short circuit between A1A+ and GND/A2A+ and GND):





P2238 and P2241 (Short circuit between A1A+ and A1A-/A2A+ and A2A-):





P2239 and P2242 (Short circuit between A1A+ and +B/A2A+ and +B):





P2252 and P2255 (Short circuit between A1A- and GND/A2A- and GND):





P2253 and P2256 (Short circuit between A1A- and +B/A2A- and +B):





CONFIRMATION DRIVING PATTERN





1. Connect the Techstream to the DLC3.

2. Turn the engine switch on (IG) and turn the Techstream on.

3. Clear the DTCs (even if no DTCs are stored, perform the clear DTC operation).

4. Turn the engine switch off and wait for at least 30 seconds.

5. Turn the engine switch on (IG) and turn the Techstream on [A].

6. Start the engine and wait 2 minutes.

7. Enter the following menus: Powertrain / Engine and ECT / Trouble Codes [B].

8. Read the Pending DTCs.

HINT
* If a pending DTC is output, the system is malfunctioning.
* If a pending DTC is not output, perform the following procedure.

9. Enter the following menus: Powertrain / Engine and ECT / Utility / All Readiness.

10. Input the DTC: P2237, P2238, P2239, P2240, P2241, P2242, P2252, P2253, P2255 or P2256.

11. Check the DTC judgment result.





HINT
* If the judgment result shows ABNORMAL, the system has a malfunction.
* If the judgment result shows INCOMPLETE or UNKNOWN, idle the engine for 3 minutes and check the DTC judgment result again [C].

12. If no pending DTC is output, perform a universal trip and check for permanent DTCs Reading and Clearing Diagnostic Trouble Codes.

HINT
* If a permanent DTC is output, the system is malfunctioning.
* If no permanent DTC is output, the system is normal.

WIRING DIAGRAM

Refer to DTC P2195 P2195.

INSPECTION PROCEDURE

HINT
Malfunctioning areas can be identified by performing the Control the Injection Volume for A/F Sensor function provided in the Active Test. The Control the Injection Volume for A/F Sensor function can help to determine whether the Air-Fuel Ratio (A/F) sensor, Heated Oxygen (HO2) sensor and other potential trouble areas are malfunctioning.

The following instructions describe how to conduct the Control the Injection Volume for A/F Sensor operation using the Techstream.

1. Connect the Techstream to the DLC3.

2. Start the engine and turn the Techstream on.

3. Warm up the engine at an engine speed of 2500 rpm for approximately 90 seconds.

4. On the Techstream, enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume for A/F sensor.

5. Perform the Active Test operation with the engine idling (press the RIGHT or LEFT button to change the fuel injection volume).

6. Monitor the output voltages of the A/F and HO2 sensors (AFS Voltage B1S1 and O2S B1S2 or AFS Voltage B2S1 and O2S B2S2) displayed on the Techstream.

HINT
* The Control the Injection Volume for A/F Sensor operation lowers the fuel injection volume by 12.5% or increases the injection volume by 25%.
* Each sensor reacts in accordance with increases and decreases in the fuel injection volume.

Standard voltage:





NOTICE:
The Air-Fuel Ratio (A/F) sensor has an output delay of a few seconds and the Heated Oxygen (HO2) sensor has a maximum output delay of approximately 20 seconds.





- Following the Control the Injection Volume for A/F sensor procedure enables technicians to check and graph the voltage outputs of both the A/F and HO2 sensors.

- To display the graph, enter the following menus: Powertrain / Engine and ECT / Active Test / Control the Injection Volume for A/F Sensor / A/F Control System / AFS Voltage B1S1 and O2S B1S1 or AFS Voltage B2S1 and O2S B2S2.

NOTICE:
Inspect the fuses for circuits related to this system before performing the following inspection procedure.

HINT
* Read freeze frame data using the Techstream. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.
* Bank 1 refers to the bank that includes the No. 1 cylinder*.
*: The No. 1 cylinder is the cylinder which is farthest from the transmission.
* Bank 2 refers to the bank that does not include the No. 1 cylinder.
* Sensor 1 refers to the sensor closest to the engine assembly.
* Sensor 2 refers to the sensor farthest away from the engine assembly.

PROCEDURE

1. CHECK HARNESS AND CONNECTOR (A/F SENSOR - ECM) P2A00

NG -- REPAIR OR REPLACE HARNESS OR CONNECTOR
OK -- Continue to next step.

2. REPLACE AIR FUEL RATIO SENSOR

(a) Replace the air fuel ratio sensor Removal.

NEXT -- Continue to next step.

3. CHECK WHETHER DTC OUTPUT RECURS

(a) Connect the Techstream to the DLC3.

(b) Turn the engine switch on (IG) and turn the Techstream on.

(c) Clear DTCs Reading and Clearing Diagnostic Trouble Codes.

(d) Start the engine.

(e) Refer to the confirmation driving pattern.

(f) Enter the following menus: Powertrain / Engine and ECT / Trouble Codes / Pending.

(g) Read pending DTCs.

Result





B -- REPLACE ECM Removal

A -- END